False error - "Could not reconnect all network drives"

In our domain we've been having a few computers displaying "Could not
reconnect all network drives" when the user logs in, but when they click on a
network drive they can access it. It seems there is an initial failure during
startup, but Windows eventually makes the connection seconds later. The
computers run Windows XP Pro and are at least 2 Ghz and 512 MB, some with 100
Megabit NICs, some with Gigabit NICs (applied DisableDHCPMediaSense registry
fix), so I don't think it's a problem with computers being too slow
authenticating on the network. Also set policy setting "Always wait for the
network...".

Is there at least a way to disable this message by policy or registry
setting. We don't need people calling the help desk when there is no issue
with connections. Thank you for any help on this.